It’s been a run of negative headlines for air carriers in recent weeks, with stories of physical altercations and questionable interactions with passengers repeatedly in the news.

Now, one passenger witness to one such event and the passenger at the center of another are voicing their frustrations, which the group helping disseminate their testimony says is in reaction to “notably absent” passenger representation from hearings in Congress about the future of air travel in the U.S.

In conjunction with a House Transportation and Infrastructure Committee hearing on Federal Aviation Administration reform, passenger advocate group Flyers Rights has released the testimony of Jason Powell, a passenger on the United Airlines flight where a fellow passenger, David Dao, was injured during a forced removal after overbooking; and Nicole Harper, whom, only a day later, says she was forced by airline staff on a separate United (NYSE: UAL) flight to urinate in a cup rather than be allowed to use the restroom.

Both are hoping Congress considers such passenger treatment as it also considers a possible move, one favored by most major airlines, to privatize the air traffic control system.

Airlines are pushing the idea because they feel it could help speed modernization and improvement of the system, something they believe has taken too long under the control of the FAA.

Among the worries of opponents, however, are that the proposed nonprofit board that would oversee the privatized system would become filled with people favorable to the needs of the airlines rather than those of its passengers.

And the passengers speaking out echoed that concern in sharing their stories.

The first, Powell, says in his written testimony provided to Congress that he is a teacher who was on the United flight with several students who all witnessed Dao being dragged off the aircraft after refusing to give up his seat after the carrier had overbooked the flight.

“ It was the worst possible model for my students, and it was truly traumatizing to many of us who watched these events from such proximity,” Powell says. “While the sense of helplessness was palpable, I was also encouraged by my fellow passengers’ protests and admonishments at the outrageous conduct they were witnessing and the bravery of some to capture the events on cell phone cameras so that the truth could emerge.”

In her own testimony, Harper, a Kansas City resident, mother and nurse, says she was more than 30 minutes into her flight — with other passengers already moving around the cabin — when, as a sufferer of overactive bladder, she made a second attempt to use the restroom after having been told to return to her seat previously.

Harper says she explained her medical condition, but was still not allowed to use the facilities.

“I was told very rudely I was not allowed to get out of my seat,” she says. “I told them I would either need to use the restroom or have a cup to pee in, I was handed two cups. Despite extreme embarrassment and violation of privacy, I was forced to urinate in the two cups in the presence of my children, husband and complete strangers.”

Harper goes on to say in the testimony, which was provided to the WBJ in an email from Flyers Rights, that her own frustration continued even after the flight and her subsequent submitted complaint as, she says, customer service did not take her seriously and that the airline issued a “completely erroneous” statement after her story became public.

That included the airline falsely claiming, in Harper’s words, that “the flight was in final descent, that they had reached out to me to better understand the situation, and they reported they did not know what I planned to do with the cups.”

It was treatment, Harper says, that made her feel victimized all over again.

In speaking out, she and Powell say they hope the government considers the treatment of passengers at a time it is also evaluating possibly giving airlines even more control than they already have.

“It seems to me that if anything, Congress should consider increasingly robust policies that hold airlines more accountable to their customers, not providing a political handout to a powerful industry that so often seems to fall short of our basic expectations,” Powell says.

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